Process for recovering aroma from tea

Abstract

Disclosed is a process for recovering volatile aroma compounds from a tea material. The process comprises the steps of: generating aroma-laden vapours at a pressure of from 0.5 to 1.4 bar absolute from the tea material contacted with water or water vapours, and then condensing the aroma-laden vapours to recover aroma condensate. The process is controlled such that the mass of aroma condensate generated per unit dry mass of tea material is greater than 2 and the aroma-laden vapours comprise no more than 1% by weight entrained liquid.

1 . A process for recovering volatile aroma compounds from a tea material comprising the steps of:
 a) generating aroma-laden vapours at a pressure of from 0.5 to 1.4 bar absolute from the tea material contacted with water or water vapours, and;   b) condensing the aroma-laden vapours to recover aroma condensate;   
     characterized in that the mass of aroma condensate per unit dry mass of tea material is greater than 2 and the aroma-laden vapours comprise no more than 1% by weight entrained liquid. 
   
   
       2 . A process as claimed in  claim 1  wherein the aroma condensate comprises no more than 0.1% of solids by weight. 
   
   
       3 . A process as claimed in  claim 1  wherein the aroma-laden vapours are passed through a liquid entrainment separator prior to the step (b) to separate the entrained liquid from aroma-laden vapours. 
   
   
       4 . A process as claimed in  claim 1  wherein an antifoam agent is added to the tea material prior to or during the step (a). 
   
   
       5 . A process as claimed in  claim 1  wherein a mechanical defoamer is used during the step (a). 
   
   
       6 . A process as claimed in  claim 1  wherein the mass of the aroma condensate generated per unit dry mass of tea material per hour is from 0.1 to 10. 
   
   
       7 . A process as claimed in  claim 1  comprising a step of incubating the tea material in an aqueous medium comprising an enzyme selected from cellulase, pectinase, amylase, β-glucosidase, primverosidase or mixture thereof, prior to the step (a). 
   
   
       8 . A mixture of volatile aroma compounds prepared by the process as claimed in  claim 1 . 
   
   
       9 . A tea composition comprising the mixture of volatile aroma compounds as claimed in  claim 8 .